Description (from application): This core is to serve four main functions: a) as a resource for foreskins and freshly cultured skin cells; b) as a source for molecular probes designed to identify tissue specific markers; c) to advise investigators in cell culture technique and help them establish cells of their interest. d) to help establish new culture techniques applicable to skin research, such as the skin equivalent procedure. The core will provide: 1. Primary cultures of normal, malignant, mutant and other abnormal cells from the same patient or different patients; 2. Co-cultures, e.g., keratinocytes/melanocytes, fibroblasts/melanocytes, keratinocytes/CTCL cells, etc. 3. Large volumes of cells for specified procedures such as the construction of cDNA libraries, analysis of genetic alterations, gene expression (mRNA), purification of cytokines, cell surface proteins, etc.; 4. the growing of cells especially those that have so far proven fastidious, such as Langerhans and CTCL cells, primary melanoma from the radial growth phase; 5) Antibodies and oligonucleotides to determine expression of markers specific for melanocytes or keratinocytes, lymphocytes and other skin cells of interest.